The government has invited us all to nominate legislation to be repealed. Where better to start than the Misuse of Drugs Act. Across Whitehall and in the medical profession, making a fresh start on the regulatory framework for drugs is probably the one thing discussed with the least publicity and the most fervour. In March, a former No 10 policy analyst, David Halpern, came out in favour of legalising heroin. The previous October, the government's chief drugs adviser, David Nutt, was sacked for arguing that some illegal drugs were less dangerous than alcohol, having already pointed out that the Home Office's precautionary principle simply made some drugs look more attractive. And it is a decade or more since the new international development minister, Alan Duncan, called for legalisation in his book Saturn's Children. Mr Duncan approached the problem as a devotee of the free market. The less ideological tackle it by trying to assess the harm – the impact on law and order of drug-related crime, for example, which accounts for four-fifths of offences like mugging and burglary. And while it was perhaps ill-advised for Professor Nutt to point out that as many deaths are related to horse riding – relatively easy to ban – as to harder-to-track illegal ecstasy use, it does not make it less true. In Britain and America, the war on drugs is now widely seen as a failure. Begin again by treating drug abuse like alcoholism and smoking – not as a matter of law and order but a question of public health.

• This article was amended on 24 May 2010. The original referred to Alan Duncan's book as Satan's Children. This has been corrected.